The present invention relates to a ceiling fan, and more particularly to an improved ceiling fan which can be remotely controlled.
In general, the conventional ceiling fan of the prior art, which can be remotely controlled, can be operate at high, medium, and low speeds. It can also be reversed. Some of the prior art ceiling fans are additionally equipped with a lighting device so as to enhance the marketability of ceiling fans.
However, the prior art ceiling fans have defects, which are further expounded explicitly hereinafter.
The operations in both forward and backward directions of the prior art ceiling fans are generally made possible by several methods. One of the methods used involves a situation, in which the operation of the fan in reverse and the stoppage of the motor take place simultaneously or in which the operation of the fan in reverse takes place while the motor stops temporarily and then resumes operation without using a detour or a bypass element. Other methods may involve several situations, in which the operation in reverse of the fan is possible only afte the fan in question has been put into a complete stop, or in which the operation in reverse of the fan can be done by following certain specified cyclic procedures, or in which the operation in reverse of the fan can be done directly without having to stop the fan in question in the first place.
The methods mentioned above are all defective in that they may bring about a fluctuation of the electric voltage, which may be four or five times greater than that of the power source, and of the electric current approaching 60 amperes or more. As a result, the motor and other components arranged along the power line are overloaded to the fluctuation of voltage and current by means of additional protective components, thereby resulting in making the power line structure too complicated and bringing about additional power consumption.
Of course, the motor can be first stopped manually by the user of the fan so as to put the fan in question into operation in reverse. However, such operating method can be quite inconvenient to the user and can result in shortening the service life of the fan by subjecting various components of the fan in question to damages.
In order to prevent the electric current supplied to the fan from fluctuating irregularly and wildly, the voltage of alternating current is first lowered to an appropriate level by means of a transformer and is subsequently rectified and filtered to become a power source in the form of direct current. But such procedures are defective in that the transformer is expensive, heavy in weight, bulky in size, and noisy, and that there is no unified specification of transformer, thereby making it difficult for the user to purchase a suitable transformer, and further that the operating transformer may raise the temperature to the extent that the service life of the components adjacent to the transformer may be adversely affected.